linux-kernel - [PATCH 5.11 181/775] media: allegro: Fix use after free on error

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20210301161210.574915391@linuxfoundation.org>
Date:   Mon,  1 Mar 2021 17:05:49 +0100
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Dan Carpenter <dan.carpenter@...cle.com>,
        Michael Tretter <m.tretter@...gutronix.de>,
        Hans Verkuil <hverkuil-cisco@...all.nl>,
        Mauro Carvalho Chehab <mchehab+huawei@...nel.org>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 5.11 181/775] media: allegro: Fix use after free on error

From: Dan Carpenter <dan.carpenter@...cle.com>

[ Upstream commit ce814ad4bb52bfc7c0472e6da0aa742ab88f4361 ]

The "channel" is added to the "dev->channels" but then if
v4l2_m2m_ctx_init() fails then we free "channel" but it's still on the
list so it could lead to a use after free.  Let's not add it to the
list until after v4l2_m2m_ctx_init() succeeds.

Fixes: cc62c74749a3 ("media: allegro: add missed checks in allegro_open()")
Signed-off-by: Dan Carpenter <dan.carpenter@...cle.com>
Reviewed-by: Michael Tretter <m.tretter@...gutronix.de>
Signed-off-by: Hans Verkuil <hverkuil-cisco@...all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@...nel.org>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 drivers/staging/media/allegro-dvt/allegro-core.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/staging/media/allegro-dvt/allegro-core.c b/drivers/staging/media/allegro-dvt/allegro-core.c
index 9f718f43282bc..640451134072b 100644
--- a/drivers/staging/media/allegro-dvt/allegro-core.c
+++ b/drivers/staging/media/allegro-dvt/allegro-core.c
@@ -2483,8 +2483,6 @@ static int allegro_open(struct file *file)
 	INIT_LIST_HEAD(&channel->buffers_reference);
 	INIT_LIST_HEAD(&channel->buffers_intermediate);
 
-	list_add(&channel->list, &dev->channels);
-
 	channel->fh.m2m_ctx = v4l2_m2m_ctx_init(dev->m2m_dev, channel,
 						allegro_queue_init);
 
@@ -2493,6 +2491,7 @@ static int allegro_open(struct file *file)
 		goto error;
 	}
 
+	list_add(&channel->list, &dev->channels);
 	file->private_data = &channel->fh;
 	v4l2_fh_add(&channel->fh);
 
-- 
2.27.0